YELLOW FEVER. 403 there are, in addition, nephritis, enteritis, albuminuria, hemoglobinuria, and hemorrhages into the body-cavities. The dog is the most susceptible animal. When it is injected intravenously the disease-process that results is almost immediately manifested with such violent symp- toms and such complex lesions as to recall the clinical and anatomical picture of yellow fever in the human being. The most prominent symptom in experimental yellow fever in the dog is vomiting, which begins directly after the penetration of the virus into the blood and con- tinues for a long time. Hemorrhages appear after the vomiting, the urine is scanty and albuminous, or there is suppression, which shortly precedes death. Once grave jaundice was observed. At the necropsy the lesions met are highly interesting, and are almost identical with those observed in man. Most conspicuous is the profound steatosis of the liver. The liver-cells, even when examined fresh, appear com- pletely degenerated into fat, this appearance correspond- ing to that found in fatal cases of yellow fever. The same result may be obtained by injecting the liver di- rectly or through the abdominal wall. The kidneys are the seat of acute parenchymatous nephritis, sometimes with marked fatty degeneration. The whole digestive tract is the seat of hemorrhagic gastro-enteritis comparable in intensity only to poisoning by cyanid of potassium. Experiments upon monkeys were also of interest, in- asmuch as they demonstrated the possibility of obtaining fatty degeneration more extensive than is observed in man. In one case the liver was transformed into a mass of fatty substance similar to wax. Goats and sheep are also very sensitive to the icteroid virus, and the lesions described also occur in them. The death of a yellow fever victim is the result of one of three causes: i. It may be due to the specific infection principally, when the Bacillus icteroides is found in the cadaver in a certain quantity and in a state of relative purity.